Doomed Speed Demos Archive
http://www.doomworld.com/sda/doom_sda.htm

Pwad:  opost21.wad by Scott Amspoker

Download link: ftp://3darchives.in-span.net/pub/idgames/levels/doom/m-o/opost21.zip 
Pwad name: Outpost 21
Map:       e2m1
Skill:     5
Category:  nightmare run

Time 1:41


Exe:       Doom.exe. The demo plays back with PRBOOM 2.2.6 and Eternity 3.31b7.
Date:      December 27, 2004
Author:    Eugene Kapustin
Email:     egk@ukr.net
HP:        no DooM related page

Outpost 21 is legendary map that was widely recognized as masterpiece from wad's release time. Four plus in the "OFFICIAL QUICK REFERENCE GUIDE FOR DOOM PWAD'S" dated May 14, 1994 and nice reviews.

I've played many PWADS over the last several weeks/months, but this is the first level that's compelled me to jump into the ring as reviewer. It's easily id-quality work.

S.P. Harvey
05/14/94

This is an amazingly good level. Every detail has been lovingly
crafted to perfection. I feel that OPOST would be quite at home in the
original suite of id episodes. Wonderfully atmospheric and very
enjoyable. It scores high marks on visual appeal, cleverness of
puzzles and playability.

Frank Stajano, DOOM Master.

05/26/94

My brother amd I've played Opost21 for the first time as e3m5 well-known Epi3best compilation. Later I find the level in several compilations:

e3m4 of Wadpak3.wad by Gary Karnik,
e1m4 of Newlev.wad by Gary Smith,
e1m4 of Wadpack3.wad from wadiii.zip archive (Episode I of this compilation coincides with Newlev.wad except e1m7 map),  
e3m7 of Megawad.wad by Nathan Lineback and
e1m6 of Hehoes.wad by Al Dewey.  

May be Opost21 is presented in EpisodXX compilations, but I can't check this now.
Forgive me if I forgot some compilations.

Demo itself is far from perfect. Keygrab needs as many as three tries. Heh. You better see my brother maxkill - op21-448. 